Split-cycle engine with dwell piston motion

Abstract

An engine includes a crankshaft having a crank throw, the crankshaft rotating about a crankshaft axis. A compression piston is slidably received within a compression cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of a four stroke cycle during a single rotation of the crankshaft. An expansion piston is slidably received within an expansion cylinder. A connecting rod is pivotally connected to the expansion piston. A mechanical linkage rotationally connects the crank throw to the connecting rod about a connecting rod / crank throw axis such that the expansion piston reciprocates through an expansion stroke and an exhaust stroke of the four stroke cycle during the same rotation of the crankshaft. A path is established by the mechanical linkage which the connecting rod / crank throw axis travels around the crankshaft axis. The distance between the connecting rod / crank throw axis and crankshaft axis at any point in the path defines an effective crank throw radius. The path includes a first transition region from a first effective crank throw radius to a second effective crank throw radius through which the connecting rod / crank throw axis passes during at least a portion of a combustion event in the expansion cylinder.

Description

[0001] Cross References to Related Applications [0002] This application claims priority to US Provisional Application No. 60 / 489,893, entitled "Cam Angle Piston Motion for Split-Cycle Engines," filed July 23, 2003, the entire contents of which are incorporated herein by reference. field of invention [0003] The invention relates to an internal combustion engine. More specifically, the present invention relates to a split-cycle engine having a pair of pistons, one for the intake and compression strokes and the other for the expansion (or drive) and discharge strokes, each of the four The stroke is completed in one crankshaft revolution. The mechanical linkage for operatively connecting the expansion piston to the crankshaft provides a very slow period of motion during a portion of the combustion cycle relative to the downward movement of the same piston pivotally connecting the connecting rod to the crankshaft through a fixed pin connection. The piston moves downward. Ba...

AI Technical Summary

Problems solved by technology

[0012] The problem is that the full thermodynamic efficiency of a typical four-stroke engine 10 is only about one-third (1 / 3)

Images